The present invention relates generally to an apparatus and method to prevent theft of motor vehicles and the like. More particularly, the invention is directed to a motor vehicle ignition security system effective to deter unauthorized starting and use of a vehicle. The problem of preventing automobile theft is one which has long challenged society, and many different systems and devices have been devised in an effort to reduce the incidence of such theft. Approaches have been varied and imaginative but, for the most part, equipment developed has been too complex and costly for general adoption.
One technique has been to install audio alarm systems. Another is the use of coded switches operating in conjunction with lock-out relays. Various types of "anti-theft" ignition system arrangements have been proposed. In still other mechanisms push button coding or combination switching arrangements have been utilized. More recently, the adoption of coded cards as ignition energization means has been urged. In spite of a compelling urgency and notwithstanding the extensive research and developmental work which has been carried out in this area, no completely satisfactory "system" or apparatus has heretofore been developed. Each approach has had objectionable features such as impractability, undue complexity, exorbitant cost, or dubious reliability. It is, accordingly, the aim of the present invention to provide a simple, low cost, yet extremely reliable vehicle ignition security apparatus which may be readily and conveniently installed, even by the vehicle owner.